Wednesday’s declines in stocks like Apple (NASDAQ:AAPL), Facebook (NASDAQ:FB) and Zynga (NASDAQ:ZNGA) show that investors are remaining glum on the tech sector, but one stock is getting especially hard-hit: Groupon (NASDAQ:GRPN).

So far in today’s trading, GRPN is down more than 8% to about $4.10, putting the stock close to its 52-week lows. More importantly, that’s coming on thick volume of 28 million — more than double its daily average …

So far, there have been no changes to the IPO calendar, which has six deals planned for this week. But the disruption from Hurricane Sandy may mean some or even all the deals will be moved to next week.

Regardless, here’s a look at each one:

1. Restoration Hardware (NYSE:RH): The luxury furniture retailer has 73 locations, a catalog sent to more than 26 million people and a website with 14 million unique visitors. Since going private in 2008, Restoration has undergone a massive transformation. For example, the company has closed down many of its mall locations and has built its Design Galleries, which are roughly 21,500 square feet. Read

In the latest expiration, 234 million shares became eligible for sale. Some of those shares apparently hitting the market, as today’s volume (as of 11 a.m.) already is above FB’s daily average of 51.8 million shares. Read

Yesterda,y Pandora’s (NYSE:P) shares fell by nearly 12% to $8.20, getting close to its 52-week low of $7.38. According to a report from Bloomberg, tech giant Apple (NASDAQ:AAPL) plans to launch an Internet radio service during the first quarter of 2013.

Right now, the company is in discussions with the major recording labels. Unsurprisingly, the big hang-up is over the sharing of the ad revenue — but Apple should be able to get a deal done.

Rather, the big issue is likely to be the service itself. Let’s face it: Apple has been a bit of a spotty lately with its apps, as seen with the mapping app and Siri. Read

But new releases from Apple (NASDAQ:AAPL) this week could be a real boon to Facebook’s renewed focus on mobile. Says CEO Mark Zuckerberg in the report:

“People who use our mobile products are more engaged, and we believe we can increase engagement even further as we continue to introduce new products and improve our platform. At the same time, we are deeply integrating monetization into our product teams in order to build a stronger, more valuable company.” Read

Child-care operator Bright Horizons — which has grown in 25 years to operate 773 child-care and early education centers, and now serves about 87,400 children in the U.S. U.K., Ireland and Canada — has filed to go public.

Bright Horizons’ core business model is to strike multi-year contracts with employers. In all, the company has 850 client relationships and boasts an impressive retention rate of 97%.

From 2001 to 2011, revenues and EBITDA grew at compound annual rates of 11% and 17%, respectively. For the first half of 2012, revenues came to $529.6 million, and EBITDA was $89.1 million. Read

Based in Silicon Valley, Tom Taulli is in the heart of IPO land. On a regular basis, he talks with many of the top tech CEOs and founders trying to find the next hot deals and finding out which start-ups are stinkers.

A long-time follower of the IPO scene, back in 1999 Tom started one of the first sites in the space called WebIPO. It was a place where investors got research as well as access to deals for the dot-com boom. Tom also wrote the top-selling book, Investing in IPOs. In it, he covers all the aspects of analyzing an IPO, such as reading the prospectus, detecting the risk factors and understanding some of the arcane regulations. But don’t worry — if that process is too intimidating for you, thankfully Tom will do the legwork for you right here in the IPO Playbook blog.

Tom is routinely quoted in the media about upcoming deals with his interviews on CNBC and Bloomberg TV, but he is eager to take your questions too. You can message him on Twitter at @ttaulli. And feel free to weigh in via the comments section on any of his IPO Playbook posts.